Lumber handling, positioning tables and feeding devices are well-known in the art. The primary drawbacks of the conventional devices are with regard to the drive mechanisms. Conventional planer infeed tables utilize canted screw rolls to move a work piece toward a fixed linebar and under a pineapple press roll. The work pieces are then shifted toward and into the planer machine. After the workpiece has reached the linebar, no further lateral forces are required. However, since the screw rolls also convey the work piece longitudinally, the lateral forces continue to force the work piece against the linebar, thus increasing the friction and drag on the work piece and reducing energy efficiency. Moreover, conventional infeed devices transport and accelerate the work piece in a disorganized manner with little or no control over the forces applied to the work pieces. This result in excessive damage to the pieces of lumber owing to the unnecessary shear forces applied to the lumber during handling.
While various diverters and re-orienteers are known in the prior art, these systems typically have not been able to perform both functions in a compact and efficient manner.
Applicant is aware of the United States Patent Application No. US 2005/0040009 entitled “Steerable Diverter System” to Ehlert, which discloses a diverter system for diverting articles being conveyed along the diverter system, which includes a plurality of diverter wheels arranged between opposite sidewalls of the diverter system. The diverter system comprises a motorized roller positioned generally beneath a row of diverter wheels and operable to rotatably drive the diverter wheels via respective ones of a plurality of drive members or bands around the motorized roller and the diverter wheels. The system may include a rack and pinion type steering system that may steer or pivot or rotate one or more rows of diverter wheels, generally in unison, in response to the rotation or pivotal movement of a pinion or drive or spur gear. The motorized roller may drive more of the wheels independently via the bands around the motorized roller and the wheels, while the shorter idler roller may drive fewer wheels via bands. In addition, rotation of the roller portion of motorized roller drives the drive members to move around the motorized roller and to independently and separately or individually rotatably drive each of the diverter wheels of row that may be positioned generally above and along the motorized roller.
The present invention was developed in order to overcome these and other drawbacks of the prior devices by providing an improved positioning table which comprises of an array of independently controlled positioning devices. The positioning devices are arrayed such that no single device supports multiple workpieces, allowing for simultaneous and independent control of each workpiece.
Among the several advantages of the present invention, it may be noted that the position and/or orientation and/or velocity and/or acceleration of individual workpieces can be actively measured and/or inferred. Other objects and features of the invention will be in part apparent and in part pointed out herein-after.